1. Field of the Invention
The invention relates in general to a charge-discharge path management circuit and method thereof, and more particularly to a battery charge-discharge path management circuit and a method thereof.
2. Description of the Related Art
With the popularity of electronic devices and rapid advance in technology, the consumers have higher and higher expectations on the functions of electronic devices and the manufacturers of electronic devices are dedicated to making electronic devices thinner, lighter and compacter so as to provide better portability to the consumers. Electronic devices are such as notebook computers. In the absence of an external power, the battery module of a portable notebook computer provides necessary power. Thus, how to make the battery module constantly supplying a steady power so that the electronic device can function normally has become a prominent task to the manufacturers. The battery module can be realized by a smart battery which has management function for providing relevant battery data such as battery status or the residual capacity of the battery.
However, the current electronic devices merely manage and communicate with the battery module through a system management bus (SMBus). That is, the electronic devices manage and communicate with the battery by software control. For example, if an electronic device is connected to an AC adaptor, the software requests the battery module to be charged, and the battery is charged accordingly. If the software does not indicate the charge-discharge status (for example, the electronic device is off the charge status) instantly after the AC adaptor is unplugged, then the battery module will be unable to judge whether to be charged (there is an AC adaptor connected to the electronic device) or to provide power. Consequently, the battery module will be pending and the electronic device may be shut down unexpectedly.